import matplotlib.colors as colors
import numpy as np
from matplotlib import cm
class MidpointRangeNormalize(colors.Normalize):
def __init__(self, vmin=None, vmax=None, midrange=None, clip=False):
self.midrange = midrange
colors.Normalize.__init__(self, vmin, vmax, clip)
def __call__(self, value, clip=None):
x = [self.vmin, self.midrange[0], self.midrange[1], self.midrange[2], self.vmax]
y = [0, 0.25, 0.5, 0.75, 1]
return np.ma.masked_array(np.interp(value, x, y))
def get_colors(colormap='hsv', n=10):
cmap = cm.get_cmap(colormap)
# First color, always black
rgb = [(0, 0, 0, 1)]
for c in np.arange(1, n):
rgb.append(cmap(c/n))
rgb = np.asarray(rgb)
# Randomize the other colors
np.random.shuffle(rgb[1:])
return rgb
